His special students, young men who fully shared his scientific life and rewarded his generosity by an affectionate devotion, knowing, perhaps, that he himself associated the completion of his book with his birthday, celebrated both events by a serenade on the eve of his anniversary. They took into their confidence Mr. Otto Dresel, warmly valued by Agassiz both as friend and musician, and he arranged their midnight programme for them. Always sure of finding their professor awake and at work at that hour, they stationed the musicians before the house, and as the last stroke of twelve sounded, the succeeding stillness was broken by men's voices singing a Bach choral. When Agassiz stepped out to see whence came this pleasant salutation, he was met by his young friends bringing flowers and congratulations. Then followed one number after another of the well-ordered selection, into which was admitted here and there a German student song in memory of Agassiz's own university life at Heidelberg and Munich. It was late, or rather early, since the new day was already begun, before the little concert was over and the guests had dispersed. It is difficult to reproduce with anything like its original glow and coloring a scene of this kind. It will no more be called back than the hour or the moonlight night which had the warmth and softness of June. It is recorded here only because it illustrates the intimate personal sympathy between Agassiz and his students. For this occasion also were written the well-known birthday verses by Longfellow, which were read the next day at a dinner given to Agassiz by the "Saturday Club." In speaking of Longfellow's relation to this club, Holmes says "On one occasion he read a short poem at the table. It was in honor of Agassiz's birthday, and I cannot forget the very modest, delicate musical way in which he read his charming verses." Although included in many collections of Longfellow's Poems, they are reproduced here, because the story seems incomplete without them. THE FIFTIETH BIRTHDAY OF AGASSIZ. It was fifty years ago, In the pleasant month of May, In the beautiful Pays de Vaud, A child in its cradle lay. And Nature, the old nurse, took The child upon her knee, Saying: "Here is a story-book Thy Father has written for thee." "Come wander with me," she said, "Into regions yet untrod; And read what is still unread In the manuscripts of God." And he wandered away and away With Nature, the dear old nurse, Who sang to him night and day The rhymes of the universe. And whenever the way seemed long, Or his heart began to fail, She would sing a more wonderful song, Or tell a more marvelous tale. So she keeps him still a child, And will not let him go, Though at times his heart beats wild For the beautiful Pays de Vaud;